Product Overview
The Socket Head Cap Screw (also referred to as a Hex Socket Head Cap Screw) is a precision-engineered fastener characterized by its cylindrical head with an internal hex drive. This design provides a high tensile and shear strength in a compact form factor, allowing for installation in tight spaces where a wrench or socket cannot fit. Ideal for machinery, fixtures, and high-stress assemblies, they offer superior clamping force and a clean, flush-to-low profile appearance.
Key Advantages
High Strength-to-Size Ratio: Delivers exceptional tensile strength (e.g., Grade 12.9) with a small head diameter.
Compact & Flush Installation: The low-profile head fits into counterbored holes, creating a smooth surface.
Superior Torque Transmission: The internal hex socket allows for higher applied torque with reduced risk of cam-out compared to some external drive types.
Versatile Drive Access: Can be driven from any angle with standard hex keys (Allen wizards) or power tools.
Full Thread & Shoulder Options: Available in fully threaded or shoulder screw designs for precise locating or bearing applications.
Material Specifications & Strength Grades
| Material Standard | Grade / Class | Typical Tensile Strength (min) | Core Hardness (HRC) | Characteristics |
|---|---|---|---|---|
| Alloy Steel | ASTM A574 (12.9) | 1220 MPa | 39-44 | Premium Grade. Highest strength, quenched & tempered. |
| Alloy Steel | ASTM A574 (10.9) | 1040 MPa | 33-39 | High Grade. Excellent strength for most demanding applications. |
| Stainless Steel | ASTM F837 (316) | 700 MPa | – | Superior corrosion resistance, good strength. |
| Stainless Steel | ASTM F837 (304) | 700 MPa | – | General purpose corrosion resistance. |
Product Series & Standards
Standard Series: Compliant with ISO 4762 (Metric), ASME B18.3 (Imperial), and DIN 912.
Sizes: Metric: M1.6 to M36. Imperial: #0 through 1″.
Drive Sizes: Precision-formed internal hex sockets matched to ISO 10664 / ASME B18.3 specifications.
Threads: Full range of coarse (UNC) and fine (UNF) pitches available.
Surface Finishes
| Finish Type | Standard / Specification | Key Properties & Notes |
|---|---|---|
| Plain (Black) | – | Basic corrosion protection, often oiled. |
| Black Oxide | MIL-DTL-13924 | Mild corrosion resistance, reduces glare, good appearance. |
| Zinc Plated (Blue/Trivalent Clear) | ASTM B633 | Good corrosion protection (72-96 hrs salt spray). RoHS compliant. |
| Electroplated Nickel | ASTM B456 | Decorative, good wear & corrosion resistance. |
| Passivation (SS) | ASTM A967 | Enhances stainless steel’s natural corrosion resistance. |
| Geomet® Coating (or equivalent) | Proprietary | High-Performance Option. Dry lubricant, consistent low friction coefficient (μ≈0.10), excellent corrosion resistance (>500 hrs salt spray). |
Quality Assurance
Every batch is manufactured under a certified ISO 9001:2015 and IATF 16949 (for automotive) quality management system. We perform dimensional inspection, hardness testing, and tensile strength verification. Full material traceability and test certificates (MTC) are available upon request.
Quality & Manufacturing
Our Socket Head Cap Screws are produced by Hebei Wohe Fastener Manufacturing Co. Ltd., utilizing advanced multi-station cold heading technology and thread rolling processes. This ensures superior grain flow and mechanical properties compared to cut threads. Our facility specializes in high-volume production of precision fasteners for demanding industries such as automotive, industrial machinery, and energy, ensuring consistent quality and reliable global supply.
Technical Support: CAD models (STEP, SAT) and comprehensive specification PDFs available.
Customization: Non-standard lengths, special threads, unique head markings, and proprietary coatings are supported.
MOQ: Standard sizes: 5,000 pcs. Prototype and small-batch orders are negotiable.
Lead Time: Standard inventory items: 10-15 days. Custom orders: 20-30 days based on specification.
All technical data is representative. Specifications such as strength ratings are dependent on material, heat treatment, and size. End-users must validate suitability for their specific application and operating conditions.
